1. A law enforcement officer commits the offense of failure to execute an arrest warrant if, with the purpose of allowing any person charged with or convicted of a crime to escape, he or she fails to execute any arrest warrant, capias, or other lawful process ordering apprehension or confinement of such person, which he or she is authorized and required by law to execute.
2. The offense of failure to execute an arrest warrant is a class A misdemeanor, unless the offense involved is a felony, in which case failure to execute an arrest warrant is a class E felony.
3. It shall be an affirmative defense to prosecution under this section that the law enforcement officer acted under exigent circumstances in failing to execute an arrest warrant on a person who has committed a misdemeanor offense under chapter 301, 302, 304, or 307 or a misdemeanor traffic offense in another state.